["European Journal of Education, Volume 61, Issue 2, June 2026. ", "\nABSTRACT\nTeacher support has been acknowledged as a significant contributor to student achievement. However, the psychological mechanism underlying this relationship, particularly the mediating role of students' self‐esteem, remains insufficiently clarified in English‐as‐a foreign‐language (EFL) learning context. In light of this, this study examined the intricate relationships between perceived teacher support, self‐esteem and academic achievement in EFL learning. Data from a cross‐sectional survey of 811 Chinese secondary school EFL students were analysed using the Set‐Exploratory Structural Equation Modelling (Set‐ESEM). The results showed that the direct effect of teacher support dimensions on EFL academic achievement was not statistically significant. Crucially, mediation analyses demonstrated that self‐esteem acted as a full mediator in the links of both emotional and instrumental support with achievement. This study not only underscored the pivotal role of self‐esteem as a core internal psychological resource for EFL learners, but also offered pedagogical implications for educators on how to foster EFL learners' balanced self‐esteem, thereby enabling teacher support to be more effectively translated into academic achievement and success.\n"]